Investigation of visual disorders of subacute myelo-optico-neuropathy (SMON) patients 32 years after onset: Questionnaire-based survey and ophthalmological examination

An investigation of subacute myelo-optico-neuropathy (SMON) patients (20 male and 132 female, aged 31–93 years) was conducted in December 1998 using a self-administered questionnaire. Following this survey, ophthalmological examinations were performed on 33 patients between 1998 and 2000. The questionnaire-based survey revealed that the prevalence of patients with cataracts was 52.0%, and those with glaucoma was 9.4%. By dividing the patients into two groups, according to the levels of visual disturbances at the time of onset of SMON, we found that the prevalence of glaucoma was higher in the group with visual disturbances than in the group with normal vision. However, the prevalence of cataracts, optico-neuritis and fundus hemorrhage was not considerably different between the two groups. Ophthalmological examinations (e.g. intraocular pressure test, visual field test, slit lamp microscopy test, funduscopic examination) revealed that 63.6% of patients had cataracts, and 12.1% had glaucoma (9.1% for normal tension glaucoma). The ophthalmological examination revealed that the prevalence of normal tension glaucoma in the SMON patients tended to be higher than in other surveys in the general population of Japan. SMON patients need follow-up ophthalmological examinations, especially for glaucoma, on a nationwide scale.